#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
double fact(int n);
int main(void)
{
	int m, n;
	double p;

	printf("Enter m,n:\n");
	scanf("%d%d", &m, &n);
	p = fact(n) / fact(n - m);
	printf("result=%.0f\n", p);

	return 0;
}

double fact(int n)
{
	int i;
	double product;

	product = 1;
	for (i = 1;i <= n;i++) {
		product = product * i;
	}

	return product;
}